Search results for " EFFICIENCY"
showing 10 items of 1091 documents
Influence of the electro-optical properties of an a-Si:H single layer on the performances of a pin solar cell
2012
We analyze the results of an extensive characterization study involving electrical and optical measurements carried out on hydrogenated amorphous silicon (α-Si:H) thin film materials fabricated under a wide range of deposition conditions. By adjusting the synthesis parameters, we evidenced how conductivity, activation energy, electrical transport and optical absorption of an α-Si:H layer can be modified and optimized. We analyzed the activation energy and the pre-exponential factor of the dark conductivity by varying the dopant-to-silane gas flow ratio. Optical measurements allowed to extract the absorption spectra and the optical bandgap. Additionally, we report on the temperature dependen…
Should TiO2 nanostructures doped with Li+ be used as photoanodes for photoelectrochemical water splitting applications?
2017
[EN] Different TiO2 nanostructures, nanotubes and nanosponges, were obtained by anodization of Ti under stagnant and hydrodynamic conditions. Samples were doped with Li+ before and after annealing at 450 degrees C during 1 h. The nanostructures were characterized by different microscopy techniques: Field Emission Scanning Electron Microscopy (FE-SEM) and Raman Confocal Laser Microscopy. Additionally, Incident Photon-to-electron Conversion Efficiency (IPCE), photoelectrochemical water splitting and stability measurements were also performed. According to the results, TiO2 nanostructures doped before annealing present the worst photocurrent response, even if compared with undoped samples. On …
Valorization of Wastewater from Table Olives: NMR Identification of Antioxidant Phenolic Fraction and Microwave Single-Phase Reaction of Sugary Fract…
2021
The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phen…
Electrochemical conversion of pressurized CO2 at simple silver-based cathodes in undivided cells: study of the effect of pressure and other operative…
2020
Abstract Electrochemical reduction of pressurized CO2 is proposed as an interesting approach to overcome the main hurdle of the CO2 electrochemical conversion in aqueous solution, its low solubility (ca. 0.033 M), and to achieve good faradaic efficiency in CO using simple sheet silver cathodes and undivided cells, thus lowering the overall costs of the process. The effect on the process of CO2 pressure (1–30 bar), current density, nature of the supporting electrolyte and other operative conditions, such as the surface of the cathode or the mixing rate, was studied to enhance the production of CO. It was shown that pressurized conditions allow to improve drastically the current efficiency o…
Artificial neural network decision support tool for assessment of the energy performance and the refurbishment actions for the non-residential buildi…
2017
The public buildings sector represents one of the most intensive items of EU energy consumption; the application of retrofit solutions in existing buildings is a crucial way to reduce its impact. To facilitate the knowledge of the energy performance of existing non-residential buildings and the choice of the more adequate actions, Public Administrations (PA) should have the availability of proper tools. Within the Italian project "POI 2007-13", a database and a decision support tool, for easy use, even to a non-technical user, have been developed. A large set of data, obtained from the energy audits of 151 existing public buildings located in four regions of South Italy have been analysed, …
A laboratory setup for the evaluation of the effects of BACS and TBM systems on lighting
2015
The paper focuses on the evaluation of the impact of Building Automation Control Systems (BACS) and Technical Building Management (TBM) systems on the performance of the lighting system in a residential building. In particular, this work shows a laboratory setup, installed at the DEIM of the University of Palermo, for simulating a typical apartment. The paper describes the laboratory, the lighting system and the BAC system installed and the test facility for evaluating the electricity consumption in presence and in absence of automation. The laboratory has been built within a research project funded by the Italian Minister of University and Research in the framework of the PON Smart Cities …
On the impact of safety requirements, energy prices and investment costs in street lighting refurbishment design
2018
Abstract Street lighting is an indispensable feature for the night landscape of cities. It is important for road safety, users visual comfort, crime prevention and to augment the perceived personal safety. Realize and maintain an adequate street lighting service is very expensive for municipalities with significant impact on their budgets. For this reason, special attention should be paid to the design of new street lighting systems and to the refurbishment of existing ones, since many of them are inadequate. In light of this it is very important to implement street lighting designs that fulfil lighting requirements avoiding energy waste and light pollution and, at the same time, result eco…
New Technologies for Adaptive Architecture
2019
Since the 1980s, the bioclimatic architecture has had the historical merit of having raised public and experts’ awareness on the importance of designing buildings with the purpose of solving the problem of energy saving. Nowadays, in the light of the most recent energy strategies policies, in force on an international and European scale, codified in EC Directive 31/2010 concerning the implementation of the Nearly Zer-Energy Buildings (NZEB), (Deru et al. 2006), the need for a new approach to redevelopment that focuses on environmental, climate and energy objectives with innovative technological solutions emerges, aimed at optimizing the passive bioclimatic behaviour of a building. In the wo…
Economic Feasibility of Measures for Energy Efficiency
2014
In this chapter the economic impact of some measures for energy efficiency, both using automation of technical infrastructures (according to EN 15232) as well as implementing passive measures concerning the use of building materials and techniques (according to EN 15271), is studied. The chapter is organized as follows. First, a technical-economical study on the evaluation of the impact on residential buildings of Building Automation Control, BAC, and Technical Building Management, TBM, systems is presented. Then the same assessment of some passive measures that can be employed is carried out using the Passive House Standard for Mediterranean warm climates is shown. Numerical elaborations h…
Special Issue “Smart Urban Lighting Systems”
2020
The design and operation of multifunctional infrastructures for public lighting as well as their impact on the urban environment and citizens’ life is today of great interest. The cost of energy for public lighting is often an issue for the budget of municipalities. Furthermore, researchers’ and designers’ attention is increasingly focused on aspects of public lighting not directly valuable through economic factors. Starting from the “quality” of the light environment, looking at citizens’ visual comfort, the light has to be considered as an instrument to improve the urban context and objects therein (including buildings). Indeed, urban degradation (lack of infrastructures, maintenance, ser…